539 research outputs found
Analytic results for two-loop Yang-Mills
Recent Developments in computing very specific helicity amplitudes in two
loop QCD are presented. The techniques focus upon the singular structure of the
amplitude rather than on a diagramatic and integration approachComment: Talk presented at 13th International Symposium on Radiative
Corrections, 24-29 September, 2017,St. Gilgen, Austria, 9 page
The Contaminated Sediment Remediation Challenge: Complicated Problems that Require Interdisciplinary and Creative Solutions
Parathyroid Hormone Hormone-Related Protein and the PTH Receptor Regulate Angiogenesis of the Skin
In developing organs, parathyroid hormone (PTH)/parathyroid hormone-related protein (PTHrP) receptor (PPR) signaling inhibits proliferation and differentiation of mesenchyme-derived cell types resulting in control of morphogenic events. Previous studies using PPR agonists and antagonists as well as transgenic overexpression of the PPR ligand PTHrP have suggested that this ligand receptor combination might regulate the anagen to catagen transition of the hair cycle. To further understand the precise role of PTHrP and the PPR in the hair cycle, we have evaluated hair growth in the traditional K14-PTHrP (KrP) and an inducible bitransgenic PTHrP mice. High levels of PTHrP trangene expression limited to the adult hair cycle resulted in the production of shorter hair shafts. Morphometric analysis indicated that reduced proliferation in the matrix preceded the appearance of thinner hair follicles and shafts during late anagen. CD31 staining revealed that the late anagen hair follicles of the KrP mice were surrounded by reduced numbers of smaller diameter capillaries as compared to controls. Moreover, the fetal skins of the PTHrP and PPR knockouts (KOs) had reciprocal increases in the length, diameter, and density of capillaries. Finally, crossing the KrP transgene onto a thrombospondin-1KO background reversed the vascular changes as well as the delayed catagen exhibited by these mice. Taken together, these findings suggest that PTHrP's influence on the hair cycle is mediated in part by its effects on angiogenesis
Analytic all-plus-helicity gluon amplitudes in QCD
We detail the calculation of two-loop all-plus helicity amplitudes for pure Yang-Mills theory.The four dimensional unitarity methods and augmented recursion techniques we have developed, together with a knowledge of the singular structure of the amplitudesallow us to compute thesein compact analytic forms.Specifically we present the computation and analytic results for the six- and seven-gluon leading colour two-loop amplitudes these being the first QCD two-loop amplitudes beyond five-points
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High-risk human papilloma virus and cervical abnormalities in HIV-infected women with normal cervical cytology
Background: The prevalence of High-Risk Human papilloma virus (HR-HPV), a necessary cause of invasive cervical cancer (ICC) is relatively high in HIV infected women. Gaps exist in our knowledge of the optimal approaches for managing women who have HR-HPV with normal cervical cytology (NCC) particularly in settings of HIV infection. Methods: Between May 2012 and June 2013 we conducted a colposcopic assessment of HIV-infected women with prior (NCC) and known HR-HPV status to compare cervical abnormalities in women with and without HR-HPV. Colposcopic examinations were done at the Operation Stop Cervical Cancer (OSCC) unit of the Jos University Teaching Hospital (JUTH), Jos, Nigeria. Abnormal colposcopic finding (ACF) was defined as areas of aceto-white epithelium involving the squamo-coulumnar junction, areas of punctation, mosaic pattern or atypical vessels. We compared proportions of ACF as well as histologic grades of cervical intra-epithelial neoplasia (CIN) in women with or without HR-HPV. Statistical analysis was done on STATA. Results: We conducted colposcopic examinations in 78 out of 89 (86.5%) eligible women. The mean age of the cohort was 32.4 years (SD ±4.6) with a median 32 years (IQR 29–36). After a mean follow up time of 20.1 months from the initial cervical pap cytology and HR-HPV testing, we found 12 of 78 (15.4%) women with ACF. The odds for an ACF was statistically higher [OR = 4.0 (95% CI: 1.1-14.7)] in women with HR-HPV compared to those without. Of the twelve women with ACF, subsequent histologic examination of colposcopically directed cervical biopsies confirmed CIN 1 in 4 cases (33.3%), CIN 2 in 1 case (8.3%), CIN 3 in 2 cases (16.7%), carcinoma-in-situ (CIS) in 2 cases (16.7%), and normal cervix in 3 (25.0%). Overall, the proportion of women detected with any grade of CIN was 11.5% (9/78) and 6.4% (5/78) were CIN 2 or greater lesion (CIN2+). Conclusion: HIV-infected women with NCC and HR-HPV had a four-fold higher likelihood for an ACF. The practice of early colposcopic examination of HIV-infected women with prior NCC and HR-HPV may increase early detection of higher grade CIN and CIS cancer stages in our setting
Development of a new real-time PCR for the detection of pilchard orthomyxovirus (POMV) in apparently healthy fish
Pilchard orthomyxovirus (POMV) is a virus of concern to the Atlantic salmon aquaculture industry in Tasmania. First isolated from wild pilchards in southern Australia in 1998, the virus is now a recognised pathogen of farmed Atlantic salmon (Salmo salar) in Tasmania. While the current real-time PCR for POMV targets segment 5 of the viral genome, recent viral gene expression data suggests that other segments of the POMV genome presented higher transcription levels and thus may be better candidates for the early detection of the virus. This study aimed to design and begin validating a more sensitive reverse transcriptase real-time PCR (RT-qPCR) assay to detect POMV. Primers and probes were developed targeting two independent viral genes derived from segments 7 and 8, which presented higher transcription levels than segment 5 in both cell culture and infected fish. These were compared with the current POMV RT-qPCR. The POMV segment 8 assay had a higher analytical sensitivity than segment 7, detecting at least 1 plasmid copy μl−1, and was 10-fold more sensitive than both POMV segment 7 and 5 assays when analysing nucleic acid from a positive field sample. Both new assays also had high analytical specificity, detecting the 11 POMV isolates tested (inclusivity testing) and not amplifying nucleic acids from other viruses, including ISAV, a related orthomyxovirus. In the latent class model analysis, the diagnostic sensitivity of the segment 8 and 7 assays were higher than segment 5 in 93% and 92% of simulations, respectively. Seven samples (18.4%), all from subclinical fish infected with POMV, returned a positive result only with the segment 8 assay. Both new assays showed reproducible results when applied to aliquots of the same samples tested in three different laboratories. The new POMV segment 8 assay shows promising results as a surveillance tool for detecting POMV in fish without any symptoms.publishedVersio
Evidence-based recommendations for the use of WBC-reduced cellular blood components
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72881/1/j.1537-2995.2001.41101310.x.pd
Association of Bacterial vaginosis and other Sexually Transmitted Infections with HIV among pregnant women in Nigeria.
OBJECTIVES: To determine the association of Bacterial vaginosis (BV) and other sexually transmissible infections (STIs) with HIV prevalence among pregnant women in Jos, Nigeria. METHODS: This was a cross- sectional study of pregnant women who participated in the Prevention of Mother-to-Child Transmission of HIV program of the AIDS Prevention Initiative in Nigeria, between April 2002 and July 2004, at the Jos University Teaching Hospital in Jos, Nigeria. Blood, high vaginal and endocervical samples were obtained for diagnosis of HIV, BV and other STIs. Data were analyzed for prevalence of HIV, BV and other STIs. Univariate and multivariate logistic regression models generated unadjusted and adjusted odds ratios (OR) as well as 95% confidence intervals (CI) of the association of BV and other STIs with HIV prevalence. P value <0.05 was considered statistically significant. RESULTS: A total of 4,046 pregnant women were studied and 97.6% (3,950/4,046) had complete laboratory records for analysis. The prevalence of HIV was 8.2% (CI: 7.4-9.1); BV 11.9% (CI: 10.9-12.9); Candida 10.7% (CI: 9.7-11.7); mixed infection of BV and Candida 2.8% (CI: 2.3-3.4); Trichomonads 0.6% (CI: 0.3-0.8) and syphilis 0.35% (0.16-0.54). BV, Candida, mixed BV and Candida; and Trichomonads were independently associated with HIV infection [adjusted OR (95% CI), 2.9 (CI: 2.2-3.9); 2.0 (CI: 1.5-2.9); 3.4 (CI: 2.0-5.6), and 3.3 (CI: 1.1-9.7) respectively]. CONCLUSION: HIV prevalence is higher among pregnant women who have BV, Candida and Trichomonads vaginal infections compared with women who have no evidence of infection. The practice of routine screening for BV and other STIs among pregnant women as a strategy for identifying women at risk for prevalent HIV infection should be sustained/ encouraged and the syndromic management of STIs should be integrated into all antenatal care management protocols in antenatal clinics in order to curb the epidemic of heterosexual HIV transmission
Association of immunophenotype with expression of topoisomerase II α and β in adult acute myeloid leukemia.
Anthracyclines used in the treatment of acute myelogenous leukemia (AML) inhibit the activity of the mammalian topoisomerase II (topo II) isoforms, topo II α and topo IIβ. In 230 patients with non-M3 AML who received frontline ara-C/daunorubicin we determined expression of topo IIα and topo IIβ by RT-PCR and its relationship to immunophenotype (IP) and outcomes. Treatment outcomes were analyzed by logistic or Cox regression. In 211 patients, available for analysis, topo IIα expression was significantly lower than topo IIβ (P \u3c 0.0001). In contrast to topo IIα, topo IIβ was significantly associated with blast percentage in marrow or blood (P = 0.0001), CD7 (P = 0.01), CD14 (P \u3c 0.0001) and CD54 (P \u3c 0.0001). Event free survival was worse for CD56-negative compared to CD56-high (HR = 1.9, 95% CI [1.0-3.5], p = 0.04), and overall survival was worse for CD-15 low as compared to CD15-high (HR = 2.2, 95% CI [1.1-4.2], p = 0.02). Ingenuity pathway analysis indicated topo IIβ and immunophenotype markers in a network associated with cell-to-cell signaling, hematological system development/function and inflammatory response. Topo IIβ expression reflects disease biology of highly proliferative disease and distinct IP but does not appear to be an independent variable influencing outcome in adult AML patients treated with anthracycline-based therapy
The First Hour of Extra-galactic Data of the Sloan Digital Sky Survey Spectroscopic Commissioning: The Coma Cluster
On 26 May 1999, one of the Sloan Digital Sky Survey (SDSS) fiber-fed
spectrographs saw astronomical first light. This was followed by the first
spectroscopic commissioning run during the dark period of June 1999. We present
here the first hour of extra-galactic spectroscopy taken during these early
commissioning stages: an observation of the Coma cluster of galaxies. Our data
samples the Southern part of this cluster, out to a radius of 1.5degrees and
thus fully covers the NGC 4839 group. We outline in this paper the main
characteristics of the SDSS spectroscopic systems and provide redshifts and
spectral classifications for 196 Coma galaxies, of which 45 redshifts are new.
For the 151 galaxies in common with the literature, we find excellent agreement
between our redshift determinations and the published values. As part of our
analysis, we have investigated four different spectral classification
algorithms: spectral line strengths, a principal component decomposition, a
wavelet analysis and the fitting of spectral synthesis models to the data. We
find that a significant fraction (25%) of our observed Coma galaxies show signs
of recent star-formation activity and that the velocity dispersion of these
active galaxies (emission-line and post-starburst galaxies) is 30% larger than
the absorption-line galaxies. We also find no active galaxies within the
central (projected) 200 h-1 Kpc of the cluster. The spatial distribution of our
Coma active galaxies is consistent with that found at higher redshift for the
CNOC1 cluster survey. Beyond the core region, the fraction of bright active
galaxies appears to rise slowly out to the virial radius and are randomly
distributed within the cluster with no apparent correlation with the potential
merger of the NGC 4839 group. [ABRIDGED]Comment: Accepted in AJ, 65 pages, 20 figures, 5 table
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